Bern Callahan, a Canadian-American author with Irish grandparents, grew up listening to stories and lore about Saint Patrick. As a young man, he was ordained a Catholic priest. Later, he embraced Tibetan Buddhism, training as a meditation teacher and Lama. Callahan's love for religion and his rich education in history and theology spurred his interest in writing Shamrock and applying a fresh vision to this ancient story.

Callahan has written a number of fiction and non-fiction books, including: The Secret Love Letters of St. Paul; Don't Wake Up! It Will Ruin Everything; and Touching the Earth: 21st Century Buddhism.

Bern lives and writes in Indian Harbour, Nova Scotia, where he shares his life with his wife, Margaret.